Building materials for construction, such as gypsum wall boards, cement boards, tiles, and roofing shingles, are typically constructed with a glass fiber mat. Chopped strand mat, suitable for use in construction materials, generally includes glass fibers because they are of high strength and tend not to shrink during use. The glass fibers are typically formed by attenuating streams of molten glass material from a bushing. The fibers are drawn from the bushing and the fibers are then chopped directly into a container. The chopped fibers are then dispersed in a water slurry which contains surfactants, viscosity modifiers, dispersants and other chemical agents. The fibers and slurry are agitated to disperse the fibers prior to depositing the mixture onto a moving screen where most of the water is removed. Although this generally describes a wet-laid process, a dry-laid process may be used. A polymeric binder is then applied. After application of the polymeric binder, the resulting mat is heated to remove the remaining water and cure the binder.
Important properties for a glass mat include surface roughness, caliper, tensile strength, and tear strength. These properties are useful in determining the efficacy of the manufacture of glass mat products and final properties of the glass mat. Modifications to the glass mats to improve such properties are desired.
Accordingly, a need continues to exist in the art for improved processes for manufacturing glass mats that can lower product cost and meet the needs of new and demanding applications.